Question

Unfortunately, many tobacco smokers diagnosed with cancer do not stop smoking, which increases their risk of mortality. A randomized controlled trial was performed to determine if extended use of varenicline should be used to treat tobacco use among cancer patients. Varenicline is a prescription medication used to treat nicotine addiction.

Using data from the following table, answer the questions that follow. Be careful…the primary outcome is a beneficial thing (smoking abstinence at 24 weeks).

	Total	7-day abstinence at 24 weeks	Serious adverse event at 24 weeks
Extended Treatment	105	40	14
Standard Treatment	102	28	9
Total	207	68	23

1. Is extended treatment associated with 7-day abstinence at 24 weeks? Calculate the correct measure of association and interpret your answer numerically.

Answer 1

Tobacco use causes 30% of cancer deaths and complicates the treatment course, and adversely affects survival rates from cancer. These deaths can be prevented or greatly reduced by screening for and treating tobacco use disorder. There are multiple medications and therapy techniques that are most effective when used in combination. Cancer patients and survivors are likely to be more dependent on nicotine than the average smoker and therefore may require more intensive approaches, including the use of multiple medications along with counselling.

The first-line pharmacotherapies for smoking cessation are nicotine replacement therapy varenicline. These treatments aim to reduce symptoms of nicotine withdrawal, thereby making it easier to stop using cigarettes. For the general population, the choice among the therapies is based largely on patient preference, with a few notable exceptions for patients with contraindications to certain drugs or comorbidities.

The mechanism by which varenicline assists smokers in achieving smoking abstinence must be understood within the context of the role that nicotine plays in fostering tobacco dependence. Nicotine is the chemical in cigarette smoke leading to addiction. Upon inhaling cigarette smoke, nicotine is quickly absorbed into the bloodstream and readily penetrates the blood–brain barrier. Nicotine subsequently acts on neuronal nicotinic acetylcholine receptors within the ventral tegmental area of the brain, causing dopamine release in the nucleus accumbens which reinforces nicotine-seeking behaviour. Nicotine is a promiscuous ligand, binding to many nicotinic acetylcholine receptor subtypes found in the central nervous system and peripheral nervous system. Human neural nicotinic acetylcholine receptors are pentameric ion channels structurally composed of 11 subunits (α₂–α₇, α₉, α₁₀, β₂–β₄). The predominant neuronal nicotinic acetylcholine receptor subtypes in the central nervous system are the α₄β₂and α₇ varieties of these, the former is most prevalent in the central nervous system, accounting for approximately 90% of central nervous system neuronal nicotinic acetylcholine receptors. This high prevalence and the high nicotine affinity of α₄β₂ neuronal nicotinic acetylcholine receptors for nicotine suggest that the α₄β₂ neuronal nicotinic acetylcholine receptor is a key bimolecular target for the perpetuation of and treatment of nicotine addiction.

Varenicline has been observed to dampen the desire to smoke. Compared with placebo, craving is significantly lower for participants who receive varenicline. Consistent with the proposed partial antagonist mechanism for varenicline, smoking satisfaction, and psychologic reward are also significantly decreased in smokers taking vareniciline.

Varenicline treatment is initiated one week prior to the patient’s target quit date. Dosing begins at 0.5 mg once daily and increases to 0.5 mg twice daily on day 4. On the target quit date (day 8), the dose is increased to 1 mg twice daily and maintained for 12 weeks.

Longer durations of therapy with varenicline have been shown to be more effective than shorter durations. In above study evaluating longer duration of therapy, participants achieving smoking abstinence at the end of treatment after 24 weeks. At the end of the extended treatment (7 day abstinence at 24 weeks) there was 40 and when serious adverse event (at 24 weeks) was 14 and while in standard it was 28 earlier and 9 in adverse event.

Vreniciline if used in adequate amount has a very good effect in patients rather than short term dose as primarily it shows better result but then lead to detachment of nicotine and then lead to again consumption of smoking tobacco, so long term its use is better in correct direction.